Module fs_watcher 

File system watcher service and other types.

The WATCHER service can be used to get notifications when a file or directory is modified. It also provides ways to bind a file to a variable, automatically synchronizing both.

The example below binds the current content of a text file to at text variable using WATCHER.read. Any external change made to the text file updates the UI text.

use zng::{fs_watcher::WATCHER, prelude::*};

Text!(WATCHER.read("dump.log", Txt::from(""), |f| f.ok()?.text().ok()))

The next example created a read-write binding with the text file, any external change made to the text file updates the TextInput! and any change made using the TextInput! updates the file contents.

use zng::{fs_watcher::WATCHER, prelude::*};

TextInput!(zng::fs_watcher::WATCHER.sync(
    "dump.log",
    // initial value
    Txt::from(""),
    // read, only updates txt if returns Some
    |f| f.ok()?.text().ok(),
    // write, only change file if commit called.
    |txt, f| {
        if let Ok(mut f) = f {
            if f.write_text(&txt).is_ok() {
                // replace actual file with temp that was successfully written.
                let _ = f.commit();
            } else {
                f.cancel();
            }
        }
    },
))

The WATCHER service abstracts away most of the headache of interacting with the file system. This service is used internally by the implementations of CONFIG and L10N.

Full API

See zng_ext_fs_watcher for the full watcher API.

Modules

fs_event

File system change event types.

Structs

FsChange

Represents a single file system change, annotated.

FsChangeNoteHandle

Handle that holds a WATCHER.annotate note.

FsChangesArgs

FS_CHANGES_EVENT arguments.

WATCHER

File system watcher service.

WatchFile

Represents an open read-only file provided by WATCHER.read.

WatcherHandle

Represents an active file or directory watcher in WATCHER.

WriteFile

Represents an open write file provided by WATCHER.sync.

Statics

FS_CHANGES_EVENT

Event sent by the WATCHER service on directories or files that are watched.

Traits

FsChangeNote

Represents a FsChange note.

IMAGES_Ext

File watcher extensions for IMAGES service.

WatcherReadStatus

Represents a status type for WATCHER read-only operations.

WatcherSyncStatus

Represents a status type for WATCHER.sync_status.